DESCRIPTION: The overall objective of the proposed studies is to identify the immune reactivity requirements of the gamma delta subset of T cells. The proposed studies will examine the role of nonpeptide antigens in gamma delta T cell expansion, and in antiviral and antibacterial activity. The studies will define the phenotypes and alkylamine antigen reactivities of gamma delta T cells from the decidua and cervix of normal women, determine the effect of alkylamine treatment on numbers and function of PB T cells from normal, SIV-infected, and BCG-infected monkeys, and determine the sequellae of such treatment on viral and bacterial pathogenesis.